How IBM Builds Blockchain for Walmart

Frank Yiannas, VP food safety at Walmart, set a challenge for his staff.

He gave them a pack of mangoes and told them to find out where they had come from. Six days, 18 hours and 14 minutes later they came back with an answer.

The mangoes had also been tracked by blockchain as part of a pilot scheme, and by looking on the blockchain finding the point of origin took just 2.2 seconds.

Before Yiannas set the challenge to his staff, he had worked with Stephen Leng, supply chain solutions portfolio and blockchain leader at IBM, to create a blockchain system to shadow Walmart’s traditional monitoring procedures as a proof of concept.

Case in point was a massive spinach salmonella outbreak that hit the US in 2015. It took weeks to resolve and spinach was cleared off shelves across the country, killing sales for that period. “When they found out where it came from, it came from one small supplier who had used the wrong process in one field,” said Leng.

Food safety was one of the first blockchain applications Leng worked on, despite the challenges. The easy option would have been to start something already semi-digitalised. Food safety, on the other hand, was “full of people, messy processes, waste and products going off”, he said.

The first proof of concept IMB and Walmart worked together on was tracking a pork supply chain in China. “[We could see] it’s been cut, it’s been processed, it’s been despatched, it was at this temperature – all of those process steps were just uplifted to the blockchain and put onto a dashboard so anyone could see them,” he said.

The team then wanted to see if they could replicate the results with a completely different product, mangoes from South America.

In this pilot, Leng’s team uploaded all suppleir certificates to the blockchain. Certificates can be a huge problem for retailers because they need to be up to date, the wording needs to be correct and they have to be audited – Walmart has more than 50 people checking certificates. The result: “We were able to display all the data around that movement of mangoes to the shelf in a very simple way,” said Leng.

IBM is not just working with Walmart on its food trust platform. There are number of participants including Kroger, Wegmans, Doll Foods, Driskel, Nestlé and Unilever, among others, and Leng predicts eventually suppliers will be told they need to be on a blockchain.

Blockchain for business has some key differences to the technology used for cryptocurrencies like Bitcoin, said Leng. It will be a closed environment where participants need to be invited onto the service and where no one can be anonymous.

Also, while cryptos use algorithmic proofs to validate transactions and maintain anonymity, on blockchain for business the validation will be done by humans approving transactions.

“The validation of the transactions and the approvals of the transactions is done by the participants of the blockchain – they’re approving it because there’s a consensus around that blockchain,” said Leng.

“It’s like a social network more than anything else, because we all have to agree,” he said.